JPH02166608A - Magnetic head for multitracks - Google Patents

Abstract

PURPOSE:To obtain the magnetic head for multitracks having excellent recording and reproducing characteristics by using a nonmagnetic material which is higher in wear rate than the core base bodies of respective head chips as spacers. CONSTITUTION:The head chips constituted by joining the base bodies 1 and the core half bodies formed on the surfaces facing the base bodies 1 via working gaps are connected in >=2 pieces via the spacers 2 consisting of the nonmagnetic material in order to simultaneously execute recording and reproducing of the plural tracks on the magnetic recording medium. The nonmagnetic which is higher in the wear rate than the core base bodies 1 of the respective head chips is used as the spacers 2. The spacers 2 wear faster than the core base bodies 1 and the worn parts are recessed to generate steps at the time of the sliding contact with the magnetic recording medium and, therefore, the load per unit area of the respective head chips increases and the contact of the plural head chips and the magnetic recording medium is well executed when the magnetic head is brought into sliding contact with the magnetic recording medium. The magnetic head for multitracks which decreases the fluctuations in the recording and reproducing characteristics and has the high reliability is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head, and more particularly to a multi-track magnetic head capable of simultaneously recording and reproducing data on a plurality of tracks on a magnetic recording medium.

[Conventional technology]

Conventionally, in this type of magnetic head, MnZn ferrite was used for the core substrate of each head chip, and barium titanate was used as a spacer to magnetically separate the core chips.

[Problem to be solved by the invention]

However, since the Mn--Zn ferrite and barium titanate have approximately the same wear rate against the magnetic recording medium, no step is formed between the core base and the spacer on the sliding contact surface even after a long period of sliding contact. For this reason, it is difficult to bring a plurality of head chips into good contact with a recording medium at the same time, and therefore it is difficult to perform good recording and reproduction on a plurality of tracks.

The purpose of the present invention is to eliminate such drawbacks of the prior art,
The object of the present invention is to provide a multi-track magnetic head with excellent recording and reproducing characteristics.

[Means to solve the problem]

To achieve the above object, the present invention provides a core half formed on a substrate and surfaces facing each other across an operating gap of the substrate in order to simultaneously record and read multiple tracks on a magnetic recording medium. In a multi-track magnetic head in which two or more head chips are connected to each other via a spacer made of a non-magnetic material, the non-magnetic material has a higher wear rate than the core substrate of each head chip. is characterized in that it is used as a spacer.

[Effect]

By adopting the above-mentioned configuration, the spacer wears out faster than the core base when it comes into sliding contact with the magnetic recording medium, and the spacer becomes concave and creates a step.

Therefore, when a magnetic head is brought into sliding contact with a magnetic recording medium, the load per unit area of each head chip increases, and good contact between a plurality of head chips and the magnetic recording medium can be achieved.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of a multi-track magnetic head according to an embodiment, in which 1 is a core base, 2 is a spacer, 3 is a metal magnetic layer, 4 is a magnetic gap, and 5 is a winding window. This embodiment shows a multi-track magnetic head having four head chips and three spacers as shown in the figure, and illustrations of windings and sliders are omitted.

Next, specific examples will be described.

(Example 1) Vickers hardness (Hv: unit Ckg/mm) was applied to the core base 1.
)) 670 single crystal Mn-Zn 7-1-lite (for example, single crystal Mn-Znn ferrite H53 manufactured by Hitachi Metals) is used, and the spacer 2 is made of non-magnetic ceramic with Hv of 510 (for example, manufactured by Nippon Electric Glass Co., Ltd.). (manufactured by MN-31) was used.

The head chip is made by forming a metal fn-type N3 with high saturation magnetic velocity density and high magnetic permeability made of an amorphous CoNb-Zr alloy by sputtering on a core substrate 1 made of MnZn ferrite. , in order to regulate the gap 4, they were bonded with low melting point glass via a SiO film.

The four Herad chips thus constructed and the spacers 2 interposed between them were adhered with synthetic resin. Further, sliders (not shown) were bonded to the head chips at both ends to complete a multi-track magnetic head.

(Example 2) The same procedure as in Example 1 was carried out, using the same material as in Example 1 for the core base 1 and using nonmagnetic ceramics with an Hv of 670 (for example, ML-07 manufactured by Nippon Electric Glass Co., Ltd.) for the spacer 2. Completed a multi-track magnetic head.

(Comparative Example 1) Single-crystal Mn Zn ferrite with Hv 670 (for example, H33 manufactured by Hitachi Metals, Ltd.) was used for the core substrate 1, and non-magnetic ceramics with Hv 800 (for example, EB-9 manufactured by Hitachi Metals, Ltd.) was used for the spacer. A multi-track (R) head was completed in the same manner as in Example 1.

〔Effect of the invention〕

A 3.5-inch magnetic disk cartridge (using a metal floppy disk with a coercive force of 1400 oersted) was installed in a recording/reproducing device equipped with each of the magnetic heads of Example 1.2 and Comparative Example 1, and a test was conducted every 2 million passes. I did it. Note that the rotational speed of the disk was 36 rpm, and the pressing load of the head was 25 g.

After this test, the level difference between the head chip and the spacer on the head sliding contact surface was measured with a roughness meter, and the change state is shown in FIG. Further, in measuring the recording and reproducing characteristics, the difference in characteristics of the four head chips and the state of change thereof with respect to the target specifications of each head chip are shown in FIG. In FIGS. 2 and 3, A with an e mark is a magnetic head of Example 1, B with a mu mark is a magnetic head of Example 2, and C with a circle mark is a magnetic head of Comparative Example 1. Further, in FIG. 2, when the spacer is concave with respect to the head chip, it is given a negative sign, and when the spacer is convex with respect to the head chip, it is given a positive sign.

As is clear from FIGS. 2 and 3, when the spacer protrudes from the head chip as in Comparative Example 1, a gap is created between the head chip and the magnetic recording medium, and one of the four head chips If an attempt is made to improve the recording and reproducing characteristics of one head chip, the contact of other head chips will deteriorate, resulting in large errors in the recording and reproducing characteristics.

On the other hand, in the case of the present invention (Example 1.2), all the spacers are concave with respect to the head chip, so all four head chips have good contact with the magnetic recording medium, and the recording and reproducing characteristics are improved. Accordingly, it is possible to provide a multi-track magnetic head with little variation in the magnetic field and high reliability.

In addition, in the examples, the materials of the core base and spacer were selected based on hardness (HV), but wear due to sliding contact is affected by factors other than hardness, such as material stickiness and ductility. Other properties, including hardness, can also differentiate spacer and core substrate wear rates.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a multi-track magnetic head according to an embodiment of the present invention, FIG. 2 is a characteristic diagram showing changes in the level difference between the Herad chip and the spacer, and FIG. 3 is a characteristic diagram showing variations in recording and reproducing characteristics. It is. １・・・・・・・・・Core base, ２・・・・・・・・・
Spacer,...Metal magnetic layer, 4...Magnetic gear. 3...

Claims (1)

[Claims] In order to simultaneously record and read multiple tracks on a magnetic recording medium, a head chip is constructed by joining a base and core halves formed on opposing surfaces of the base via an operating cap. , a multi-track magnetic head in which two or more magnetic heads are connected via a spacer made of a non-magnetic material, characterized in that a non-magnetic material having a higher wear rate than the core base of each head chip is used as the spacer. magnetic head.